/Engine/Source/Runtime/Json/Public/Dom/JsonObject.h
Try to get the field named FieldName as an object, or return false if it's another type
bool TryGetObjectField ( const [FString](API\Runtime\Core\Containers\FString) & FieldName, const [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FJsonObject](API\Runtime\Json\Dom\FJsonObject) > *& OutObject ) const